1. Field of the Invention
The invention relates generally to self-test and/or self-diagnostic systems used with emergency battery packs which provide emergency functions for lighting fixtures including fluorescent lighting fixtures, the invention particularly relating to a modular self-diagnostic assembly configured as an add-on accessory for existing emergency lighting packs without the need for modification of such packs.
2. Description of the Prior Art
Standard lighting fixtures such as fluorescent lighting fixtures are commonly provided with an emergency lighting capability by installation of appropriate inverter circuitry in the form of xe2x80x9cbattery packxe2x80x9d systems as are described inter alia in U.S. Pat. No. 5,202,608 and 5,814,971 to Johnson, these patents being subject to assignment to the present assignee, Acuity Brands, Inc., of Atlanta, Ga., doing business in the lighting industry under the name of Lithonia Lighting. The patents to Johnson describe circuitry embodied in fluorescent emergency battery packs known in the industry under the trademark xe2x80x9cPower Sentryxe2x80x9d, the present invention being configured to provide a self-test or self-diagnostic function to the emergency battery packs of the Power Sentry series as well as to emergency battery packs generally as are known in the art. The ability to test and perform diagnosis of failures in such battery packs has become a desirable practice in the industry. Previously available self-test or self-diagnostic capability has taken the form of circuitry incorporated into the emergency lighting pack itself, this prior circuitry typically acting to test proper function of inverter circuitry including charging circuitry as well as battery and lamp status. Such circuitry typically functions through use of a test switch electrically connected to the circuitry which is to be tested so that a test button or the like can be manually operated to accomplish the testing function. Timing circuitry of conventional configuration is also known in the art for automatically performing testing and diagnostic functions at specified intervals, such circuitry typically being integrated into the emergency pack and being configured within a common housing containing inverter and other circuitry comprising the emergency pack. Integration of testing and/or diagnostic circuitry directly into that circuitry comprising the inverter function and housed by a single housing has required modification to such emergency battery packs both structurally and electrically. Retrofitting of existing packs with self-diagnostic circuitry has been difficult at best in prior art practice in view of the necessity for modification of existing packs to accommodate such circuitry. A need has thus existed in the industry for an advance that allows an emergency capability to be provided to a standard lighting fixture through installation of an emergency pack to which a self-diagnostic function can be incorporated without the need for modification of the pack. This need exists in newly installed lighting systems as well as in retrofit situations where lighting fixtures are already in place having emergency packs operable with such fixtures.
Conventional fluorescent emergency lighting packs ordinarily provide for manual testing of such packs by means of an externally connected test switch and indicator lamp electrically connected to a high voltage AC power input of the pack. Operation of such a test switch simulates a power failure so that a user can test and confirm operation of the pack under the simulated conditions of an emergency, that is, the loss of mains power. Such conventional indicators verify that a battery of a conventional pack is in a charging state. Indicators of this type are located within the emergency pack housing except for at least a portion of the indicator lamp which extends from the pack at a location convenient for viewing by a user who is manually testing the pack. As described in U.S. patent application Ser. No. 09/865,913, filed May 24, 2001, the patent application being subject to an assignment to Acuity Brands, Inc., a test switch and indicator is provided with a separate housing externally of the pack housing and is connected electrically and mechanically through insulated leads and a suitable connector to an emergency pack, the switch and indicator being electrically connected to a low voltage portion of the emergency pack as dictated in the pending patent application identified above, the test switch and indicator being mounted on a printed circuit board and contained by an appropriate housing which is preferably formed of a plastic material. The connector described in the patent application also acts to enable inverter circuitry of the emergency pack for emergency operation and further to prevent the pack when the connector is not connected to the pack from operating in the event AC power is not present. The invention of the patent application reduces product cost and simplifies external wiring.
A prior emergency lighting system embodying the teachings of U.S. Pat. No. 5,416,384 to Bavaro incorporates a battery module and a power module, the power module acting to operate a lamp when AC mains power is available to the lighting system while the battery module drives lamping when AC mains power is absent such as occurs during emergency conditions. This prior lighting system does not provide the advantages occasioned by the present invention in that a self-test and/or self-diagnostic module is not provided by the prior system. The prior system does not therefore provide the capability of incorporating a self-test and/or self-diagnostic function into an existing emergency lighting pack without modification to the pack whether in a new installation or in a retrofit situation.
Accordingly, the present invention provides utility not found in existing emergency lighting systems by providing teachings including dense multi-board assembly, large product packaging, dedicated product formats and the ability to upgrade previously installed packs with self-test and/or self-diagnostic capabilities. The present invention provides advantages not previously available in the art through embodiment of a modular system concept wherein self-test and/or self-diagnostic circuitry is contained within a module housing and connected through a lead and connector assembly to a low voltage portion of an existing emergency pack, the self-test/self-diagnostic module being further connected by a lead and connector assembly to a test switch and indicator module contained by a housing separate from the module housing containing the self-test and/or self-diagnostic circuitry. While the modular concept of the invention can include various self-test and/or self-diagnostic circuitry including known circuitry, the invention is preferably provided with circuitry particular to the invention for control and other functions including power conversion, boost enable and automatic self-configuration on determination of the nature of a battery forming a portion of an emergency pack.
The invention provides in a modular form self-test and/or self-diagnostic circuitry contained within a housing and forming a portion of an emergency lighting system and having the ability to impart self-test/self-diagnostic function to emergency lighting packs used to incorporate emergency capability into standard lighting systems. According to the invention, a housing containing the self-test and/or self-diagnostic circuitry is separate from structure housing circuitry and components of an emergency lighting pack to which the self-test and/or self-diagnostic circuitry adds the testing and/or diagnostic function. Functions including charging and transfer functions are also provided by circuitry housed within the diagnostic module, the diagnostic module being an add-on accessory to existing emergency lighting packs without the need for modification of such lighting packs.
The diagnostic module of the invention further provides particular circuitry contained within the diagnostic module for accomplishment of diagnostic and control functions although it is to be recognized that conventional or other circuitry capable of providing necessary diagnostic, control and other functions can be utilized as the circuitry contained in the diagnostic module of the invention. Functions produced by circuitry contained within the diagnostic module of the invention include performance of manual or scheduled tests such as by means of low voltage operation, cooperation with a test switch and indicator lamp located externally of the diagnostic module, conversion of battery voltage levels present in battery structures housed within an emergency lighting pack to a regulated DC voltage of a predetermined level, detection of the on and off state of lamping of the lighting system for postponement of scheduled tests, and automatic self-reconfiguration for operation with battery structures of differing voltages.
The diagnostic module of the invention operates in concert with a separately contained test switch and indicator lamp external of the module and connected to the module by conventional leads and a connector. The test switch and indicator lamp permit manual testing of the emergency lighting pack through connection with the diagnostic module to produce a visual indication of the operational worthiness of the pack.
Accordingly, it is an object of the invention to provide a self-contained module capable of accomplishment of self-test and/or self-diagnostic and other functions indicative of an acceptable potential for operation of an emergency lighting pack or emergency battery pack which imparts an emergency capability to standard lighting fixtures and particularly to ballasted fluorescent lighting fixtures, the module being separate from the pack and connectable to the pack without modification of the pack, thereby permitting incorporation of the test and diagnostic functions to packs installed as original equipment or as retrofitting to a previously installed pack.
It is another object of the invention to provide a modular system incorporating the functions of an emergency battery pack within a first module, self-test and/or self-diagnostic as well as control and other functions within a second module, and a test switch and indicator lamp module, the modules being interconnected by appropriate leads and connectors and functioning to impart an emergency capability to standard lighting fixtures.
It is a further object of the invention to provide control functions within a diagnostic module which are provided through the agency of one or more microprocessors to convert battery voltage levels within a given range to a regulated DC voltage of a predetermined level.
It is yet another object of the invention to provide a diagnostic module with the ability to automatically reconfigure itself to operate with emergency lighting packs having differing battery voltages.
It is a still further object of the invention to provide a self-contained module capable of accomplishment of self-test/self-diagnostic and other functions indicative of an acceptable potential for operation of an emergency lighting pack, the module containing particular circuitry capable of test, diagnostic, control and other functions necessary and desirable to operation of the emergency pack and the lighting fixture to which the pack imparts emergency capability.
It is another object of the invention to provide a self-contained module capable of accomplishment of self-test/self-diagnostic and other functions indicative of an acceptable potential for operation of an emergency lighting pack which comprises any useful circuitry capable of necessary and desirable functioning of the pack and the lighting fixture to which the pack imparts emergency capability.
Further objects and advantages of the invention will become more readily apparent in light of the following detailed description of the preferred embodiments.